Attendance module completed

* Updated __name__ to payroll.attendance
* Updated date to utc
* New clean __init__.py
* New clean tryton.cfg
* hr.xml deleted as it is of no use
Merge pull request #10 from tarunbhardwaj/master

Updated attendance.py, attendance.xml, tryton.cfg and deleted hr.xml
Update __init__.py
reolved conflict
Added validations to the fields